xref: /dpdk/app/test/test_atomic.c (revision 2f45703c17acb943aaded9f79676fd56a72542b2)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
5  *   All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <stdio.h>
35 #include <stdint.h>
36 #include <unistd.h>
37 #include <sys/queue.h>
38 
39 #include <rte_memory.h>
40 #include <rte_memzone.h>
41 #include <rte_per_lcore.h>
42 #include <rte_launch.h>
43 #include <rte_atomic.h>
44 #include <rte_eal.h>
45 #include <rte_per_lcore.h>
46 #include <rte_lcore.h>
47 
48 #include "test.h"
49 
50 /*
51  * Atomic Variables
52  * ================
53  *
54  * - The main test function performs three subtests. The first test
55  *   checks that the usual inc/dec/add/sub functions are working
56  *   correctly:
57  *
58  *   - Initialize 16-bit, 32-bit and 64-bit atomic variables to specific
59  *     values.
60  *
61  *   - These variables are incremented and decremented on each core at
62  *     the same time in ``test_atomic_usual()``.
63  *
64  *   - The function checks that once all lcores finish their function,
65  *     the value of the atomic variables are still the same.
66  *
67  * - The second test verifies the behavior of "test and set" functions.
68  *
69  *   - Initialize 16-bit, 32-bit and 64-bit atomic variables to zero.
70  *
71  *   - Invoke ``test_atomic_tas()`` on each lcore: before doing anything
72  *     else. The cores are waiting a synchro using ``while
73  *     (rte_atomic32_read(&val) == 0)`` which is triggered by the main test
74  *     function. Then all cores do a
75  *     ``rte_atomicXX_test_and_set()`` at the same time. If it is successful,
76  *     it increments another atomic counter.
77  *
78  *   - The main function checks that the atomic counter was incremented
79  *     twice only (one for 16-bit, one for 32-bit and one for 64-bit values).
80  *
81  * - Test "add/sub and return"
82  *
83  *   - Initialize 16-bit, 32-bit and 64-bit atomic variables to zero.
84  *
85  *   - Invoke ``test_atomic_addsub_return()`` on each lcore. Before doing
86  *     anything else, the cores are waiting a synchro. Each lcore does
87  *     this operation several times::
88  *
89  *       tmp = rte_atomicXX_add_return(&a, 1);
90  *       atomic_add(&count, tmp);
91  *       tmp = rte_atomicXX_sub_return(&a, 1);
92  *       atomic_sub(&count, tmp+1);
93  *
94  *   - At the end of the test, the *count* value must be 0.
95  */
96 
97 #define NUM_ATOMIC_TYPES 3
98 
99 #define N 10000
100 
101 static rte_atomic16_t a16;
102 static rte_atomic32_t a32;
103 static rte_atomic64_t a64;
104 static rte_atomic64_t count;
105 static rte_atomic32_t synchro;
106 
107 static int
108 test_atomic_usual(__attribute__((unused)) void *arg)
109 {
110 	unsigned i;
111 
112 	while (rte_atomic32_read(&synchro) == 0)
113 		;
114 
115 	for (i = 0; i < N; i++)
116 		rte_atomic16_inc(&a16);
117 	for (i = 0; i < N; i++)
118 		rte_atomic16_dec(&a16);
119 	for (i = 0; i < (N / 5); i++)
120 		rte_atomic16_add(&a16, 5);
121 	for (i = 0; i < (N / 5); i++)
122 		rte_atomic16_sub(&a16, 5);
123 
124 	for (i = 0; i < N; i++)
125 		rte_atomic32_inc(&a32);
126 	for (i = 0; i < N; i++)
127 		rte_atomic32_dec(&a32);
128 	for (i = 0; i < (N / 5); i++)
129 		rte_atomic32_add(&a32, 5);
130 	for (i = 0; i < (N / 5); i++)
131 		rte_atomic32_sub(&a32, 5);
132 
133 	for (i = 0; i < N; i++)
134 		rte_atomic64_inc(&a64);
135 	for (i = 0; i < N; i++)
136 		rte_atomic64_dec(&a64);
137 	for (i = 0; i < (N / 5); i++)
138 		rte_atomic64_add(&a64, 5);
139 	for (i = 0; i < (N / 5); i++)
140 		rte_atomic64_sub(&a64, 5);
141 
142 	return 0;
143 }
144 
145 static int
146 test_atomic_tas(__attribute__((unused)) void *arg)
147 {
148 	while (rte_atomic32_read(&synchro) == 0)
149 		;
150 
151 	if (rte_atomic16_test_and_set(&a16))
152 		rte_atomic64_inc(&count);
153 	if (rte_atomic32_test_and_set(&a32))
154 		rte_atomic64_inc(&count);
155 	if (rte_atomic64_test_and_set(&a64))
156 		rte_atomic64_inc(&count);
157 
158 	return 0;
159 }
160 
161 static int
162 test_atomic_addsub_and_return(__attribute__((unused)) void *arg)
163 {
164 	uint32_t tmp16;
165 	uint32_t tmp32;
166 	uint64_t tmp64;
167 	unsigned i;
168 
169 	while (rte_atomic32_read(&synchro) == 0)
170 		;
171 
172 	for (i = 0; i < N; i++) {
173 		tmp16 = rte_atomic16_add_return(&a16, 1);
174 		rte_atomic64_add(&count, tmp16);
175 
176 		tmp16 = rte_atomic16_sub_return(&a16, 1);
177 		rte_atomic64_sub(&count, tmp16+1);
178 
179 		tmp32 = rte_atomic32_add_return(&a32, 1);
180 		rte_atomic64_add(&count, tmp32);
181 
182 		tmp32 = rte_atomic32_sub_return(&a32, 1);
183 		rte_atomic64_sub(&count, tmp32+1);
184 
185 		tmp64 = rte_atomic64_add_return(&a64, 1);
186 		rte_atomic64_add(&count, tmp64);
187 
188 		tmp64 = rte_atomic64_sub_return(&a64, 1);
189 		rte_atomic64_sub(&count, tmp64+1);
190 	}
191 
192 	return 0;
193 }
194 
195 /*
196  * rte_atomic32_inc_and_test() would increase a 32 bits counter by one and then
197  * test if that counter is equal to 0. It would return true if the counter is 0
198  * and false if the counter is not 0. rte_atomic64_inc_and_test() could do the
199  * same thing but for a 64 bits counter.
200  * Here checks that if the 32/64 bits counter is equal to 0 after being atomically
201  * increased by one. If it is, increase the variable of "count" by one which would
202  * be checked as the result later.
203  *
204  */
205 static int
206 test_atomic_inc_and_test(__attribute__((unused)) void *arg)
207 {
208 	while (rte_atomic32_read(&synchro) == 0)
209 		;
210 
211 	if (rte_atomic16_inc_and_test(&a16)) {
212 		rte_atomic64_inc(&count);
213 	}
214 	if (rte_atomic32_inc_and_test(&a32)) {
215 		rte_atomic64_inc(&count);
216 	}
217 	if (rte_atomic64_inc_and_test(&a64)) {
218 		rte_atomic64_inc(&count);
219 	}
220 
221 	return 0;
222 }
223 
224 /*
225  * rte_atomicXX_dec_and_test() should decrease a 32 bits counter by one and then
226  * test if that counter is equal to 0. It should return true if the counter is 0
227  * and false if the counter is not 0.
228  * This test checks if the counter is equal to 0 after being atomically
229  * decreased by one. If it is, increase the value of "count" by one which is to
230  * be checked as the result later.
231  */
232 static int
233 test_atomic_dec_and_test(__attribute__((unused)) void *arg)
234 {
235 	while (rte_atomic32_read(&synchro) == 0)
236 		;
237 
238 	if (rte_atomic16_dec_and_test(&a16))
239 		rte_atomic64_inc(&count);
240 
241 	if (rte_atomic32_dec_and_test(&a32))
242 		rte_atomic64_inc(&count);
243 
244 	if (rte_atomic64_dec_and_test(&a64))
245 		rte_atomic64_inc(&count);
246 
247 	return 0;
248 }
249 
250 static int
251 test_atomic(void)
252 {
253 	rte_atomic16_init(&a16);
254 	rte_atomic32_init(&a32);
255 	rte_atomic64_init(&a64);
256 	rte_atomic64_init(&count);
257 	rte_atomic32_init(&synchro);
258 
259 	rte_atomic16_set(&a16, 1UL << 10);
260 	rte_atomic32_set(&a32, 1UL << 10);
261 	rte_atomic64_set(&a64, 1ULL << 33);
262 
263 	printf("usual inc/dec/add/sub functions\n");
264 
265 	rte_eal_mp_remote_launch(test_atomic_usual, NULL, SKIP_MASTER);
266 	rte_atomic32_set(&synchro, 1);
267 	rte_eal_mp_wait_lcore();
268 	rte_atomic32_set(&synchro, 0);
269 
270 	if (rte_atomic16_read(&a16) != 1UL << 10) {
271 		printf("Atomic16 usual functions failed\n");
272 		return -1;
273 	}
274 
275 	if (rte_atomic32_read(&a32) != 1UL << 10) {
276 		printf("Atomic32 usual functions failed\n");
277 		return -1;
278 	}
279 
280 	if (rte_atomic64_read(&a64) != 1ULL << 33) {
281 		printf("Atomic64 usual functions failed\n");
282 		return -1;
283 	}
284 
285 	printf("test and set\n");
286 
287 	rte_atomic64_set(&a64, 0);
288 	rte_atomic32_set(&a32, 0);
289 	rte_atomic16_set(&a16, 0);
290 	rte_atomic64_set(&count, 0);
291 	rte_eal_mp_remote_launch(test_atomic_tas, NULL, SKIP_MASTER);
292 	rte_atomic32_set(&synchro, 1);
293 	rte_eal_mp_wait_lcore();
294 	rte_atomic32_set(&synchro, 0);
295 
296 	if (rte_atomic64_read(&count) != NUM_ATOMIC_TYPES) {
297 		printf("Atomic test and set failed\n");
298 		return -1;
299 	}
300 
301 	printf("add/sub and return\n");
302 
303 	rte_atomic64_set(&a64, 0);
304 	rte_atomic32_set(&a32, 0);
305 	rte_atomic16_set(&a16, 0);
306 	rte_atomic64_set(&count, 0);
307 	rte_eal_mp_remote_launch(test_atomic_addsub_and_return, NULL,
308 				 SKIP_MASTER);
309 	rte_atomic32_set(&synchro, 1);
310 	rte_eal_mp_wait_lcore();
311 	rte_atomic32_set(&synchro, 0);
312 
313 	if (rte_atomic64_read(&count) != 0) {
314 		printf("Atomic add/sub+return failed\n");
315 		return -1;
316 	}
317 
318 	/*
319 	 * Set a64, a32 and a16 with the same value of minus "number of slave
320 	 * lcores", launch all slave lcores to atomically increase by one and
321 	 * test them respectively.
322 	 * Each lcore should have only one chance to increase a64 by one and
323 	 * then check if it is equal to 0, but there should be only one lcore
324 	 * that finds that it is 0. It is similar for a32 and a16.
325 	 * Then a variable of "count", initialized to zero, is increased by
326 	 * one if a64, a32 or a16 is 0 after being increased and tested
327 	 * atomically.
328 	 * We can check if "count" is finally equal to 3 to see if all slave
329 	 * lcores performed "atomic inc and test" right.
330 	 */
331 	printf("inc and test\n");
332 
333 	rte_atomic64_clear(&a64);
334 	rte_atomic32_clear(&a32);
335 	rte_atomic16_clear(&a16);
336 	rte_atomic32_clear(&synchro);
337 	rte_atomic64_clear(&count);
338 
339 	rte_atomic64_set(&a64, (int64_t)(1 - (int64_t)rte_lcore_count()));
340 	rte_atomic32_set(&a32, (int32_t)(1 - (int32_t)rte_lcore_count()));
341 	rte_atomic16_set(&a16, (int16_t)(1 - (int16_t)rte_lcore_count()));
342 	rte_eal_mp_remote_launch(test_atomic_inc_and_test, NULL, SKIP_MASTER);
343 	rte_atomic32_set(&synchro, 1);
344 	rte_eal_mp_wait_lcore();
345 	rte_atomic32_clear(&synchro);
346 
347 	if (rte_atomic64_read(&count) != NUM_ATOMIC_TYPES) {
348 		printf("Atomic inc and test failed %d\n", (int)count.cnt);
349 		return -1;
350 	}
351 
352 	/*
353 	 * Same as above, but this time we set the values to "number of slave
354 	 * lcores", and decrement instead of increment.
355 	 */
356 	printf("dec and test\n");
357 
358 	rte_atomic32_clear(&synchro);
359 	rte_atomic64_clear(&count);
360 
361 	rte_atomic64_set(&a64, (int64_t)(rte_lcore_count() - 1));
362 	rte_atomic32_set(&a32, (int32_t)(rte_lcore_count() - 1));
363 	rte_atomic16_set(&a16, (int16_t)(rte_lcore_count() - 1));
364 	rte_eal_mp_remote_launch(test_atomic_dec_and_test, NULL, SKIP_MASTER);
365 	rte_atomic32_set(&synchro, 1);
366 	rte_eal_mp_wait_lcore();
367 	rte_atomic32_clear(&synchro);
368 
369 	if (rte_atomic64_read(&count) != NUM_ATOMIC_TYPES) {
370 		printf("Atomic dec and test failed\n");
371 		return -1;
372 	}
373 
374 	return 0;
375 }
376 
377 REGISTER_TEST_COMMAND(atomic_autotest, test_atomic);
378